<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script src="lib/react.js"></script>
    <script src="lib/react-dom.js"></script>
    <script src="lib/browser.js"></script>
</head>
<body>
    

    <div  id="root"></div>

    <script  type="text/babel">


       function formatName(user) {
        return user.firstName + ' ' + user.lastName;
        }

        const user = {
        firstName: 'Harper',
        lastName: 'Perez'
        };

        const element = (
        <h1>
            Hello, {formatName(user)}!
        </h1>
        );

        ReactDOM.render(
        element,
        document.getElementById('root')
        );

    </script>
</body>
</html>